Announcement to Michelle Users

Jean-Rene Roy, Associate Director Gemini North

29 May 2003

During the past several weeks progress has been made at the Joint Astronomy Center towards
preparing Michelle for the June and July 2003 observing runs. Successful work recently completed
includes the repair of a broken connection on the Michelle detector that was the cause of a
dead channel. Adjustment to the Michelle fore-optics to compensate for a misalignment discovered
during the February 2003 commissioning run was also attempted. Unfortunately, the detector is
still affected with significant vignetting on two of its sides and an additional re-work is required.
We are planning this work to be done in July and August.

Given that many of the Michelle commissioning tasks still need to be completed and that we
expect some remaining issues with telescope integration, there is no remaining time for science
in 2003A. Consequently, we announce the cancellation of the 2003A Michelle queue programs. The
affected PIs, National Gemini Offices and National TACs have been informed of this decision.

However, we have identified a few Michelle programs in the 2003A queue that we would like to
use for Michelle engineering. We would use these programs to verify the functionality of
Michelle and to complete many of the outstanding commissioning tasks. We would ensure that the observations
have as much science value as possible given the constraints of using science programs in an
engineering mode. Affected PIs will be contacted in due course.

We plan to complete enough commissioning of the instrument between now and October to be in
a position to execute regular Michelle Queue programs starting in November 2003. We will
work closely with ITAC and the NTACs to identify the programs that would be best suitable
for this period.